decodable.swift

extension Decodable {
	static func oneOf(json: AnyObject, objects: (Decodable.Type)...) throws -> Decodable {
		for decodable in objects.dropLast() {
			if let decoded = try? decodable.decode(json) {
				return decoded
			}
		}
		return try (objects.last!).decode(json)
	}
}